do recursive bit inside foreachfield codegen

src/utils.jl

@@ -28,25 +28,40 @@ else
  const _getproperty = getproperty
 end
 
-function _foreachfield(names, L)
+array_names_types(::Type{StructArray{T, N, C, I}}) where {T, N, C, I} = array_names_types(C)
+array_names_types(::Type{NamedTuple{names, types}}) where {names, types} = zip(names, types.parameters)
+array_names_types(::Type{T}) where {T<:Tuple} = enumerate(T.parameters)
+
+function apply_f_to_vars_fields(names_types, vars)
+ exprs = Expr[]
+ for (name, type) in names_types
+ sym = QuoteNode(name)
+ args = [Expr(:call, :_getproperty, var, sym) for var in vars]
+ expr = if type <: StructArray
+ apply_f_to_vars_fields(array_names_types(type), args)
+ else
+ Expr(:call, :f, args...)
+ end
+ push!(exprs, expr)
+ end
+ return Expr(:block, exprs...)
+end
+
+function _foreachfield(names_types, L)
  vars = ntuple(i -> gensym(), L)
  exprs = Expr[]
  for (i, v) in enumerate(vars)
  push!(exprs, Expr(:(=), v, Expr(:call, :getfield, :xs, i)))
  end
- for field in names
- sym = QuoteNode(field)
- args = [Expr(:call, :_getproperty, var, sym) for var in vars]
- push!(exprs, Expr(:call, :f, args...))
- end
+ push!(exprs, apply_f_to_vars_fields(names_types, vars))
  push!(exprs, :(return nothing))
  return Expr(:block, exprs...)
 end
 
-@generated foreachfield_gen(::NamedTuple{names}, f, xs::Vararg{Any, L}) where {names, L} =
- _foreachfield(names, L)
-@generated foreachfield_gen(::NTuple{N, Any}, f, xs::Vararg{Any, L}) where {N, L} =
- _foreachfield(Base.OneTo(N), L)
+@generated foreachfield_gen(::NT, f, xs::Vararg{Any, L}) where {NT<:NamedTuple, L} =
+ _foreachfield(array_names_types(NT), L)
+@generated foreachfield_gen(::T, f, xs::Vararg{Any, L}) where {T<:Tuple, L} =
+ _foreachfield(array_names_types(T), L)
 
 foreachfield(f, x::StructArray, xs...) = foreachfield_gen(fieldarrays(x), f, x, xs...)